Film and cameras that are all in one, commonly referred to as single-use or one-time-use cameras, have recently become well known. Typically, the single-use camera is a simple point-and-shoot type comprising a plastic, inner, main body part which supports a fixed-focus taking lens, a film metering mechanism, a manual film advance thumbwheel, a single-blade shutter, a manual shutter release button, a frame counter for indicating the number of exposures remaining for picture-taking, a direct see-through viewfinder, and possibly an electronic flash unit. Plastic front and rear casing or cover parts house the main body part between them to form a light-tight camera unit. A decorative cardboard outer box contains the camera unit and has respective openings for the taking lens, the shutter release button, the film advance thumbwheel, the viewfinder, the frame counter, and a flash emission window.
At the manufacturer, the main body part is loaded with a 12, 24, or 36 exposure 35 mm film cartridge, and the front and rear casing parts are connected to each other and/or to the main body part to assemble a-light-tight camera unit. Then, an exposed end of a take-up spool in the main body part is rotated to factory prewind substantially the entire length of the unexposed filmstrip from the cartridge shell or housing onto the spool. Lastly, the outer box is placed on the camera unit.
After the photographer takes a picture with the single-use camera, he or she manually rotates the thumbwheel to rotate a cartridge spool inside the cartridge shell to rewind the exposed frame into the cartridge shell. The rewinding movement of the filmstrip the equivalent of slightly more than one frame width rotates a metering sprocket in engagement with the filmstrip to decrement the frame counter to its next lower-numbered setting. When the maximum number of exposures available on the filmstrip are exposed and the filmstrip is completely rewound into the cartridge shell, the single-use camera is given to a photofinisher who tears the outer box off the camera unit, separates the rear cover part from the main body part, and removes the film cartridge with the filmstrip from the main body part. Then, he removes the filmstrip from the cartridge shell to develop the negatives and make prints for the customer, and he forwards the used camera parts to the manufacturer for recycling, i.e. remanufacture.
To remove the filmstrip from the cartridge shell, it is customary to break open the cartridge shell or insert a manual film extractor inwardly through a light-trapping slit in the cartridge shell to engage a leading film end of a film roll on the cartridge spool. The tighter the wrap of the film roll about the cartridge spool, the more difficult it is for the manual film extractor to engage the leading film end because of the tendency of the leading film end to curl against the film roll.